This article was originally published in British Strength Magazine. You can subscribe for free at www.britishstrengthmagazine.com
Many of us don't breathe as efficiently as we are designed to do and as we take a breath between 5000 and 15000 times a day a mechanism that is designed to be effortless at rest can actually create a lot of stress throughout our body. This brief article will give a quick overview of how to spot if you have any tell tale signs of breathing dysfunction and underline the importance of diaphragm function.
Bordoni & Zanier (2013) sum up the the importance of the diaphragm pretty succinctly “the diaphragm not only plays a role in respiration but also has many roles affecting the health of the body. It is important for posture, for proper organ function, and for the pelvis and floor of the mouth. The diaphragm muscle should not be seen as a segment but as part of a body system.”
Breathing is an action that requires the synchronisation and coordination of multiple muscles depending on the level of physical exertion that you are undertaking at the time. During periods of high exertion the primary muscles of inhalation and exhalation get some help from accessory muscles (some of these can be seen in the picture below). It is common to see imbalances and lack of coordination in a persons breathing that come from injuries, old traumas, emotional stresses or postural factors.
There are a number of signs we look for in clinic that indicate if someone is breathing efficiently or not. We will look at the depth and frequency of breathing, the visible presence of an aortic pulse in the abdomen, rib flaring, any hypertonicity (tight muscles) in the neck, abdominals, lower or upper back and so on which are involved in breathing, we will also ask questions about relevant injuries that will likely have had an impact on your breathing. The right hand picture below shows what happens to your back and hip position when the diaphragm takes on a more postural role. The diaphragm flattens superiorly due to it increasing its tension on its attachments to the lumbar spine to create stability that it has lost.
In order for the diaphragm to not take on a postural role you need to be able to create enough intra-abdominal pressure through the lumbar core to stabilise yourself: transversus abdominus; rectus abdominus; multifidus; quadratus lumborums and; internal and external obliques (notice how almost all of these muscles are also involved in the breathing mechanism itself). It's through the loss of the ability to create enough stability with these muscles that individuals often start bracing with their diaphragms. Muscles and the systems they are involved in should be able to fire efficiently regardless of whether you happen to be breathing in or out at the time. If they can't and you are bracing your diaphragm or holding your breath to carry out day to day tasks then that is going to start to affect your global mechanics by changing your rib cage and lumbar spine position. So a lot of the work that is done in clinic with clients is aimed at dissociating the diaphragm from the postural role and also getting the lumbar core musculature back involved with the breathing mechanism efficiently in order to rebuild efficient intra-abdominal pressure.
The diaphragm has 3 peripheral attachments: the lumbar vertebrae (R side L1, 2, 3, L side L1, 2); costal cartilages ribs 7-12; and xiphoid process (base of sternum). The muscle fibres combine to form a central tendon that attaches to the inferior pericardium. There are fascial attachments to: the abdominals; greater psoas; quadratus lumborum; spinal erectors; TVA; cremaster; pyramidalis; internal and external obliques; and the rectus abdominis. Posteriorly it has attachments to: the inferior vena cava; aortic system; liver; phrenic-oesophogeal ligaments; and the kidneys. Additionally there are fascial connections to the cervical spine via the transversalis fascia and also through to the musculature that comprise the posterior oblique sling. It is also of vital importance in the vascular and lymphatic systems. So when there is dysfunction in the diaphragm or any of the connecting fascia then there will be problems in some or all of these structures. So some conditions that the respiratory diaphragm may be involved in (excluding those with a structural or diagnosed medical cause) include: acid reflux; chronic or sudden onset of hiccups; IBS; indigestion; chest pain, back pain whilst coughing, sneezing or hiccuping, thoracic outlet syndrome, neck pain, and many more.
The respiratory diaphragm is mirrored in its action by the pelvic floor during respiration. These two structures are part of our intrinsic core and help to steady the trunk and also influence and control bowl and urinary function. In addition pelvic floor function has been noted to influence respiratory function – this has particular reference to any women who have had a C-section or episiotomy. It is not a coincidence that women who have had a C-section are twice as likely to experience back pain than those who had a natural birth. Further these areas are connected to the same motor neurons which influence the muscles of the floor of the mouth and so can affect and be affected by hyoid function (this may manifest as neck problems, difficulty swallowing, voicebox problems etc).
Breathing also plays a huge role in the nervous state of our bodies. The body attempts to keep homeostasis (a balance between the fight or flight (sympathetic) and rest and recover (parasympathetic) nervous systems). When we inhale we are in a sympathetic, or excitatory state, and when we exhale our body relaxes and is in a parasympathetic state. Having a balance between these two and being able to switch between fight or flight and rest and recover is of primary importance. Diaphragm function can have a direct impact on the vagus nerve and therefore vagal tone. The vagus nerve (the 10th cranial nerve which originates in the medulla oblongata) gives input to the parasympathetic part of the autonomic nervous system (ANS) which serves to regulate homeostasis throughout our bodies and actively inhibits and regulates some high energy functions. This input is sub-conscious and continuous. 'Vagal tone' is used as a marker for how 'stressed' our parasympathetic nervous system or ANS is and the body needs to have a balance between the sympathetic and parasympathetic nervous systems. Getting stuck in a sympathetic state, or on the in breath, leads to increased stress and is thought to be a symptom of an underactive vagus nerve.
This inability for the body to exhale and relax properly can lead to things such as chronic fatigue and fibromyalgia, and can be present for a number of different reasons. It is quite common to find people in this 'up regulated' state where they will possibly be agitated, struggle to relax, may have difficulty sleeping or wake up regularly through the night, and have a lower tidal volume and higher residual volume than you might expect.
Due to all of its attachments and intimacy with the vagus nerve the diaphragm is a very common 'go to' to help other muscles work more efficiently, this is particularly the case for the 'core' musculature to which it is attached. Your body creates compensations to enable it to work better at that moment and bracing of the diaphragm is often a very effective way at getting things to work better when they struggle to work for themselves, leading to the diaphragm taking on a more postural role changing the posture of the spine – this then has potential knock on effects all around the body.
The importance of having a happy diaphragm is hard to overstate due to its position within the body and the influence that it can exert. The improvements that can be made to an individuals system when you can improve the efficiency of their breathing are far ranging. From increased athletic performance, to be able to move without pain, from reducing full body stress and anxiety to reducing the dependence on medication in some cases of chronic breathing conditions such as asthma. It may also offer an explanation in some cases for acid reflux, IBS, constantly needing to go to the toilet, why you suffered a hernia, and many, many more.
This article has focused on the anatomical significance and importance of the diaphragm and some common, easy to spot things that would indicate that your breathing mechanics perhaps aren't as great as they could be. In the second part to this article we will discuss some good tools that can be used to help make your diaphragm happy if it is currently in an unhappy state, some breathing drills, and techniques to separate your diaphragm from taking on too much of a postural role.